Rob,
I PM'ed Tim that we got Cat O' Mine under 8 feet bridge clearance to do the Lachine Canal through Montreal by removing the HDX24 radar dome while leaving up a radar platform a bit above the Coleman 13.5 BTU Coleman rooftop air conditioner we had at the time. Boat is in the shop so I can't do exact measurements, but I think with 13.5 rooftop AC he'll be an inch or inch and a half under 8 feet bridge clearance even with a radar platform just above the AC.
If not, Tim could add 900 lbs of gas, plug the aft cockpit scuppers and add 400 lbs of water to each sponson while disabling the bilge pump floats, and three 300 lb 'good ol' boys' with strong wrists and their 150 lbs of beer and a Sarasota astronomical low tide and squeeze under.
Since I can't measure, if other TC255 owners have a more precise reassurance, sing out! I'm depending on memory, and it's not what it used to be.
What was the subject again?
Cheers!
John